Ruby + Graphs with Neo4j

Tag Archives: graph database

If you’ve been following my blog for a while, you probably know I like using YourKit and Gatling for testing end to end requests in Neo4j. Today however we are going to do something a little different. We are going to be micro-benchmarking a very small piece of code within our Unmanaged Extension using a Java library called JMH.

A few months ago, Mark Needham blogged about how to setup remote monitoring of Neo4j using YourKit. I was asked the other day about getting a few more details on how to do this on Amazon, so here is my attempt at that. The first thing we’ll do is setup Neo4j on a Virtual Private Cloud. It’s good practice to not put your databases directly on the public internet.Continue reading →

I started my software development career writing applications for a Call Center at a small bank in Florida. I remember the bank had purchased whatever the “Cadillac” of Interactive Voice Response (IVR) systems was then for some crazy amount of money. Today you can build an IVR overnight using Twilio.

When you sign up with Twilio, you get to choose your phone number (more or less). For example, I picked +1 (636) 451-7411, which spells out +1 (neo) 4j1-7411. If you were to call this number right now (assuming I have not run out of Twilio credits) you’ll connect to my IVR.Continue reading →

A while ago, I showed you a way to scale Neo4j writes using RabbitMQ. Which was kinda cool, but some of you asked me for a different solution that didn’t involve adding yet another software component to the stack.

Turns out we can do this in just Neo4j using a little help from the Guava library. The solution involved a background service running that holds the writes in a queue, and every once in a while (like say every second) commits those writes in one transaction.Continue reading →

I’m on Kickstarter to ask for your help in order to create a set of videos to teach you how to build high performance Neo4j applications. I am going to capture the lessons I’ve learned over the past 4 years working with graph databases and share them with you.

These videos will teach you everything you need to know about building high performance applications using Neo4j.Continue reading →

About 6 months ago we looked at how to translate a few lines of Cypher in to way too much Java code in version 1.9.x. Since then Cypher has changed and I suck a little less at Java, so I wanted to share a few different ways to translate one into the other just in case you stuck in a mid-eighties time warp and are paid by the number of lines of code you write per hour.

Just because you can, doesn’t mean you should. However sometimes it can be comforting to know how. I am going to show you how to run Neo4j Embedded and Neo4j Server at the same time…and an Unmanaged Extension inside that Neo4j Server. There aren’t any real good reasons why you’d want to do this, but it’s April Fools, so here we go.

Sometimes you’ll find yourself looking at a traversal and thinking… “I’m going to be doing this one thing over and over again.” That sounds kind of wasteful and years of recycling have taught us not to be wasteful. Let’s take a look at an example from our past. Look back at the Neo Love application, the one with the picture of Marilyn Monroe and Groucho Marx. Let’s see what a Neo4j 2.0 version of that query would look like:

In the last blog post we saw how we could get about 1,250 requests per second (with a 10ms latency) using an Unmanaged Extension running inside the Neo4j server… but what if we wanted to go faster?

The easy answer is to Scale Up. However, trying to add more cores to my Apple laptop doesn’t sound like a good time. Another answer is running a Neo4j Cluster and (almost) linearly scaling our read requests as we add more servers. So a 3 server cluster would give us between 3,500 and 3,750 requests per second.

But can we go faster on a single server without new hardware? Well… yes.Continue reading →